Harvest and Storage

Onion and Garlic

Harvesting and Storing Onion and Garlic

Discusses harvesting, curing and storing onion and garlic to include Elephant garlic.

Potatoes - "Irish"

Harvesting and Storing Potatoes

Discusses harvesting, curing and storing white ("Irish") potatoes.

Problems, Diseases and Insects

The Preparation of Small Quantities of Pesticide Sprays

Pesticide labels often provide application rates on a per acre or 100 gallon basis. This web page provides conversions for mixing smaller quantities of sprays.

Beans

Curly Top Virus is typically associated with tomato, is also a problem for beans. Photos of snap beans and pinto beans identified as positive for this virus are shown.

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Beets

Curly Top Virus is typically associated with tomato, is also a problem for beets. A photos of beets identified as positive for this virus are shown.

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Onions

Frozen onions

Onion bulbs freeze at 30 to 32 F.; however, they can withstand temperatures as low as 23 F without damage as long as they are not moved before they thaw. Less injury occurs when thawed at 39 to 41 F than at higher temperatures. Onions only slight frozen may recover with little perceptible injury if allowed to thaw slowly and without handling.

Iris Yellow Spot Virus (tospovirus)

Iris Yellow Spot Virus (tospovirus), was identified in northern Colorado in September 2001. Serological tests were positive for Iris Yellow Spot Virus (tospovirus). This virus is transmitted by various species of thrips, including onion thrips. The disease has a host range which includes onion, garlic, leek, and iris. It has been reported on onion in Israel, Brazil, Idaho, and Utah.

Distribution and Incidence of Iris yellow spot virus in Colorado and Its Relation to Onion Plant Population and Yield

This report, written by David Gent, Howard Schwartz, and Rajiv Khosla of Colorado State University, appeared in the May 2004 issue of Plant Disease. This journal is published by the American Phytopathological Society.

Fusarium Basal Rot Susceptibility

Yield information and susceptibility to Fusarium basal rot (caused by Fusarium oxysporum f. sp. cepae) of onion varieties grown in Western Colorado is provided.

2001 Data

2002 Data

2003 Data

Pink Root Susceptibility

Pink root, caused by Phoma terrestris (syn. Pyrenochaeta terrestris) can be a serious problem in commercial onion fields. Pink root is reported to reduce yields and bulb size. In this study, twenty six onion varieties were examined for their susceptibility to pink root.

2001 Data

2002 Data

2003 Data

Thrips Research

2000 - Chemical Control of Onion Thrips - Fruita, CO

Two insecticide trials conducted near Fruita in 2000 demonstrated that onion thrips are at least partially resistant to two formulations of Warrior insecticide. Lannate LV was partially effective in controlling onion thrips, but control was only 53% and 60% at five and ten days after treatment. The combination of Lannate and Warrior was no more effective than Lannate alone. The lack of effective insecticides for onion thrips control is cause for concern for onion producers in the future.

2001 - Onion Variety Tolerance to Thrips Feeding, Fruita CO

Twenty onion varieties were planted in 2001 in Western Colorado in a replicated trial to determine relative tolerance to thrips feeding. Discussion and results.

2003 - Onion Insecticide Trials

Two insecticide trials were conducted at the Western Colorado Research Center at Fruita to evaluate several classes of insecticide against onion thrips. The first trial evaluated methyl anthranalate, an insect feeding stimulant, with each insecticide. The second trial evaluated Lannate LV and Spinosad in combination with surfactants or methyl anthranalate.

2004 - Onion Insecticide Trials

An evaluation of labeled and currently unlabeled insecticides was conducted on onion thrips, Thrips tabaci, in a red onion (cv 'Flare') field at the Jerry Hines Farm, located on California Mesa, southwest of Delta Co. Ten materials and/or combinations plus an untreated control were tested.

2005 IR4 Onion Thrips Insecticide Trials

Two insecticide trials were conducted on Mesa County CO onion thrips in 2005. A foliar insecticide trial evaluated 15 insecticides and/or rates of mostly unlabeled materials to determine their suitability for inclusion in the IR4 minor crops pesticide registration program. A seed / planting time treatment evaluated 7 treatments for activity against onion thrips through bulbing.

Western Colorado Thrips

This guide shows characteristics which are useful in differentiating onion thrips, Thrips tabaci, from western flower thrips, Frankliniella occidentalis.

For further information on onion diseases, and for the weekly onion update visit the Colorado State University VegNet for Onions.

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Peppers

Curly Top Virus is typically associated with tomato, is also a problem for peppers. Photos of other vegetablesidentified as positive with this virus are shown.

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Potato

Growth Cracks, Malformations and PinkEye

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Squash and Pumpkin

Viruses

Yellowing of leaves, stunting and death of plants, and distortion of leaves and fruit are often caused by viruses. A discussion of common virus problems and insect vectors is included along with photographs of symptoms.

Curly Top Virus, typically associated with tomato, is a problem for squash and pumpkin. Photos of plants identified as positive for this virus are shown.

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Sweet Corn

The High Plains Disease

A discussion of this virus-like disease, including photographs of symptoms is provided.

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Tomato

Curly top Virus

Curly top is one of several insect-vectored viral diseases that affect tomatoes. Seventy-five percent losses can occur in Western Colorado when conditions are favorable for the spread of the beet leafhopper (Circulifer tenellus), the vector of the virus responsible for this disease.

Tomato Spotted Wilt Virus

TSWV is best recognized by the yellow splotches and yellow bulls-eye like rings on ripe tomato fruit. Other hosts, the vector, control options and photographs of symptoms is available at this site.

Blossom-end Rot - A common Problem of Tomato, Pepper and Summer Squash

This disorder is caused by a deficiency in calcium, a water-soluble element. The resulting dehydration of the cells explains the parchment-like appearance of the affected tissue. In some cases, the dead tissue is colonized by fungus producing a moldy appearance.

Production and care

Climatic Data for the Tri River Area

The length of growing season, as well as the average last spring frost and average first fall frost are critical to gardening success. Data is provided for various communities in the Tri River Area - Western Colorado.

Vegetable and Flower Fertility Needs

The fertility of vegetables should be based on a soil test. This page provides general guidance on what nutrients are needed.

Hardening Transplants

The transplanting process can be a shock to rapidly growing seedlings especially when set out into the cold windy garden in the spring. Young seedlings can be made somewhat resistant to heat, cold temperatures, drying and whipping winds, certain types of insect injury, injury from blowing sand and soil particles and low soil moisture by a process termed "hardening".

Hardiness Zone Map for the Tri River Area

The portion of the USDA Hardiness Zone Map covering the Tri River Area - Western Colorado has been reproduced for your convenience.

National Standards for the Production, Handling, and Processing of Organically Grown Agricultural Products (The National Organic Program)

This final ruling details the methods, practices and substances that can be used in producing and handling organic crops and livestock, as well as processed products. It establishes clear organic labeling criteria, and specifically prohibits the use of genetic engineering methods, ionizing radiation, and sewage sludge for fertilization.

Colorado's contact is Don Gallegos, Colorado Department of Agriculture, 700 Kipling Street Suite 4000, Lakewood, CO 80215-5894 (303) 239-4149

Onion Response To AuxiGro

Tests were initiated with AuxiGro on onions at two locations during the 2002 growing season to determine if onion size could be increased.

Western Colorado Onion Variety Trials - Yield

Yield information of onion varieties grown in research plots Western Colorado is provided.

2000 Data

2001 Data

2002 Data  

2003 Data

Vegetable Transplants - timetable

Vegetables transplants should be started in the home, greenhouse or hotbed based on the recommended age of the transplant for planting to the garden and the date of the average last spring freeze. Information is provided on temperature requirements and length of time required to produce vegetable transplants.

Vegetable Planting Times

Vegetables can be divided into two general groups - cool season vegetables and warm season vegetables. Information is provided on vegetables basing the time of planting on frost-free dates and cold-hardiness of vegetables.

Planting Vegetables during the Winter for an early Spring crop

Some cold-hardy vegetables can be planted late in the fall and during the winter months in temperate zone climes to take advantage of early spring germination and development. An explanation of this technique is provided.

Long-term storage of Vegetable Seeds

Vegetable seed can often be stored for up to ten years if dried and treated properly. Specifics are given on this technique.